Transfluxor integrator



A ril 7, 1964 A. s. ROBINSON TRANSF'LUXOR INTEGRATOR Filed May 28, 1958I liENTOR. ARTHUR S RDB/NSON United States Patent O 3,128,388TRANSFLUXOR HNTEGRATOR Arthur S. Robinson, Allendale, N.J., assignor toThe Bendix Corporation, a corporation of Delaware Filed May 28, 1958,Ser. No. 738,491 2 Claims. (Cl. 307-438) This invention relates tointegrators in which information may be stored and read out at any time.

Electro-mechanical devices have been used for integrating heretofore,but for aircraft applications the electromechanical devices areunsatisfactory because they are too heavy and bulky.

One object of this invention is to provide a reliable electric circuitwhich integrates electric signals and stores the result indefinitely andprovides non-destructive readout.

Another object of the invention is to provide an integrating circuitwhich is compact, light weight, inexpensive to manufacture and has nofunctionally moving parts.

The invention contemplates an integrating circuit having memory andnon-destructive readout comprising a transfluxor initially magnetized toa predetermined level and adapted to be connected to a source ofalternating current for energizing the transfiuxor and to alow-impedance source of pulsating signal voltage for changing the levelof magnetization according to the instantaneous polarity of the signalvoltage by an amount corresponding to the amplitude and duration of thesignal voltage, the transfiuxor providing an output corresponding to thelevel to which the transfluxor is magnetized, and means connected to thetransfluxor for providing an output corresponding to the level ofmagnetization of the transfluxor from the predetermined level.

The foregoing and other objects and advantages of the invention willappear more fully hereinafter from a consideration of the detaileddescription which follows, taken together with the accompanying drawingswherein one embodiment of the invention is illustrated by way ofexample. It is to be expressly understood, however, that the drawingsare for illustration purposes only and are not to be construed asdefining the limits of the invention.

In the drawings:

FIGURE 1 is a diagram of a novel integrator constructed according to theinvention and shows waveforms of the input signal and integrated outputsignal; and

FIGURES 2 and 3 show the novel integrator used as a 7 low pass filterand a high pass filter, respectively.

The novel integrator constructed according to the invention and shown inFIGURE 1 comprises a transfiuxor 11 having a core 9 with a winding 8thereon adapted to be connected to a source of direct current 10 forinitially magnetizing the core for preconditioning the core by firstraising the level of magnetization to completely block the core and thenreducing the magnetization to a predetermined level preferably midwaybetween completely blocked and completely unblocked to providebidirectional operation of the core. For this purpose a pair ofsimultaneously operated three-position switches 12 are interposedbetween the winding 8 and source It). The switches are moved to position12" to connect winding 8 directly to source 10 to completely block thecore of the transfluxor. The switches then are moved to position 12" toreverse the polarity of the source with respect to the winding andinsert a resistor 14 in series with winding 8 to provide current flowthrough the winding in an opposite direction and of lesser magnitudethan heretofore to decrease the magnetization level preferably midwaybetween completely blocked and completely unblocked as described above.Switch 12 is then moved to position 12 to disconnect winding 8 fromsource 10 and the trans- "ice fluxor is ready to perform theintegration. Resistor 14 determines the level of magnetization of thecore and may be adjusted to provide any desired initial level ofmagnetization of the core.

A phase sensitive demodulator 1 is connected to a source of modulatedcarrier signals, not shown, and provides a direct current correspondingto the amplitude and phase of the modulated carrier signals. The directcurrent signal then passes through a diode gate circuit 3 which providessignal pulses with a repetition rate and duration as a function of oneor more variable conditions or parameters such as Mach number, altitude,etc., and a voltage drive circuit 5 which provides a low impedancesource. Drive circuit 5 is connected to a setting or control winding 7on core 9 which incrementally increases or decreases the magnetizationof the core, depending on the instantaneous polarity of the signalvoltage applied to winding 7, by an amount corresponding to theamplitude and duration of each signal pulse applied; and the totalincrease or decrease in the magnetization of the core depends on therepetition rate of the pulses and the length of time the pulses areapplied.

A primary or energizing winding 13 on core 9 is energized by a source ofalternating current 15 and induces an output in a secondary winding 17on core 9 which corresponds to the level of magnetization of core 9. Theoutput from winding 17 is applied through a peak detector circuit 21 toa modulator 19 energized by an alternating current source 20. Peakdetector circuit 21 supplies direct current to modulator 19corresponding to the output of winding 17.

Since the transfluxor core is initially partially magnetized, asdescribed above, to provide bidirectional operation, a voltage buckingcircuit 23 at the output of modulator 19 provides an initial zerooutput. Circuit 23 comprises a source of alternating current voltage 25,out-of-phase with source 20, connected across a primary winding 27 of atransformer 29, having its secondary winding 31 connected to modulator19 and arranged to oppose the output from the modulator. Source 25 isadjusted to cancel the initial output from modulator 19 to zero theintegrator.

Graph b--b shows the integrated signal waveform corresponding to aninput signal a-a' at the input of the circuit. It will be observed thatthe phase of the carrier in graph b-b' does not reverse until theintegral of the signal goes to zero. The phase of the output carrierdefines the sign of the integral and depends entirely on the amplitudeof the transfluxor output with respect to the amplitude of source 25.

In FIGURE 2 the integrator circuit of FIGURE 1 is shown in use as a lowpass filter. The input signal and filtered output are shown by graphs 0and d, respectively.

FIGURE 3 shows the integrator circuit used as a high pass filter andgraphs e and 1 show the input signals and filtered output, respectively.

The novel circuit disclosed provides an integrating device withoutmoving parts capable of infinite memory and non-destructive readout andwhich is easily manufactured, compact and light weight.

Although but a single embodiment of the invention has been illustratedand described in detail, it is to be expressly understood that theinvention is not limited thereto. Various changes may also be made inthe design and arrangement of the parts without departing from thespirit and scope of the invention as the same will now be understood bythose skilled in the art.

What is claimed is:

1. An integrating circuit having memory and non-destructive readoutcomprising a transfiuxor having a core magnetized to a predeterminedlevel and having a control amount corresponding to the amplitude andduration "of j the signahan energizing winding on the core adapted to beconnected to" a source'of alternating current and an output winding onthe core inductively coupled to 'the L' energizing winding by' anamount'corresponding to the level to which the core is magnetized,means'conne'cted to the output Winding for detecting the peak voltage ofthe output and providing a sine wave of predetermined frequencymodulated by the peak output voltage, and means connected to the lastmentioned means for providing an output corresponding to the level ofmagnetization of the core from the predetermined level.

2. An integrating circuit having memory and non-destructivereadout'comprising a low impedance source including a gate circuitoperated as a function of a variable parameter and adapted to beconnected to a source of sigrial voltage to provide signal pulses with arepetition rate and duration as a function of a variable condition, atransfluxor having a core magnetized to a predetermined level, a controlwinding on the core'co'nnected to the gate -circuit for changing thelevel of magnetization of thecore according to the instantaneouspolarity of the signal pulses and by an amount corresponding to theamplitude and duration of the signal pulses, an energizing winding onthe core adapted to be connected to a source of alternating current, andan output Winding on the core inductively coupled to the energizingwinding and providing an output corresponding to the level to which thecore is magnetized, means connected to the output winding for detectingthe peak voitage of the output and providing a sine wave ofpredetermined frequency modulated by the peak output voltage, and meansconnected to the last mentioned means for opposing a predeterminedportion of the sine wave output.

'Refere'nces Cited in the file of this patent UNITED STATES" PATENTSOTHER REFERENCES Publication: The Transfluxor, Rajchmartand L0,Proceedings of the IRE, March 1956, pp. 321-332.

1. AN INTEGRATING CIRCUIT HAVING MEMORY AND NON-DESTRUCTIVE READOUTCOMPRISING A TRANSFLUXOR HAVING A CORE MAGNETIZED TO A PREDETERMINEDLEVEL AND HAVING A CONTROL WINDING, A LOW IMPEDANCE SOURCE OF PULSATINGSIGNAL VOLTAGE CONNECTED TO THE CONTROL WINDING FOR CHANGING THE LEVELOF MAGNETIZATION OF THE CORE ACCORDING TO THE INSTANTANEOUS POLARITY OFTHE SIGNAL VOLTAGE AND BY AN AMOUNT CORRESPONDING TO THE AMPLITUDE ANDDURATION OF THE SIGNAL, AN ENERGIZING WINDING ON THE CORE ADAPTED TO BECONNECTED TO A SOURCE OF ALTERNATING CURRENT AND AN OUTPUT WINDING ONTHE CORE INDUCTIVELY COUPLED TO THE ENERGIZING WINDING BY AN AMOUNTCORRESPONDING TO THE LEVEL TO WHICH THE CORE IS MAGNETIZED, MEANSCONNECTED TO THE OUTPUT WINDING FOR DETECTING THE PEAK VOLTAGE OF THEOUTPUT AND PROVIDING A SINE WAVE OF PREDETERMINED FREQUENCY MODULATED BYTHE PEAK OUTPUT VOLTAGE, AND MEANS CONNECTED TO THE LAST MENTIONED MEANSFOR PROVIDING AN